The present invention relates to a drilling device of the type used for drilling in rock or earth layers or similar. More specifically the invention relates to a drilling device which is suitable for drilling with long drill strings comprising a large number of drill string elements which may have somewhat different lengths.
In prior art drilling devices, e.g. for exploration drilling, of the kind which the present invention aims at improving it is important for achieving good efficiency in the handling of the drill string to have two operators, one who handles the drilling machine and one who handles the drill string elements. In exploration drilling this handling is very time-consuming since one takes up drill samples every third meter or so and the drill string comprises several hundred drill string elements.